LOCAL_MODULE_TAGS 选项说明

LOCAL_MODULE_TAGS ：=user eng tests optional
user: 指该模块只在user版本下才编译
eng: 指该模块只在eng版本下才编译
tests: 指该模块只在tests版本下才编译
optional:指该模块在所有版本下都编译

如果两次make之间选了不同的编译模式，则需要运行一下make installclean，确保本次make不会用到上次install的文件，也可以运行make clean，不过耗时较长。

eng This is the default flavor. A plain “make” is the same as “make eng”. droid is an alias for eng.
* Installs modules tagged with: eng, debug, user, and/or development.
* Installs non-APK modules that have no tags specified.
* Installs APKs according to the product definition files, in addition to tagged APKs.
* ro.secure=0
* ro.debuggable=1
* ro.kernel.Android.checkjni=1
* adb is enabled by default.

user “make user” This is the flavor intended to be the final release bits.
* Installs modules tagged with user.
* Installs non-APK modules that have no tags specified.
* Installs APKs according to the product definition files; tags are ignored for APK modules.
* ro.secure=1
* ro.debuggable=0
* adb is disabled by default.

userdebug “make userdebug” The same as user, except:
* Also installs modules tagged with debug.
* ro.debuggable=1
* adb is enabled by default.

Build flavors/types
When building for a particular product, it’s often useful to have minor variations on what is ultimately the final release build. These are the currently-defined “flavors” or “types” (we need to settle on a real name for these).
eng This is the default flavor. A plain “make ” is the same as “make eng “. droid is an alias for eng .
Installs modules tagged with: eng , debug , user , and/or development .
Installs non-APK modules that have no tags specified.
Installs APKs according to the product definition files, in addition to tagged APKs.
ro.secure=0
ro.debuggable=1
ro.kernel.android.checkjni=1
adb is enabled by default.
user “make user ”
This is the flavor intended to be the final release bits.
Installs modules tagged with user .
Installs non-APK modules that have no tags specified.
Installs APKs according to the product definition files; tags are ignored for APK modules.
ro.secure=1
ro.debuggable=0
adb is disabled by default.
userdebug “make userdebug ”
The same as user , except:
Also installs modules tagged with debug .
ro.debuggable=1
adb is enabled by default.
If you build one flavor and then want to build another, you should run “make installclean ” between the two makes to guarantee that you don’t pick up files installed by the previous flavor. “make clean ” will also suffice, but it takes a lot longer.